Buy Saddlemen Expandable Sissy Bar Bag Luggage S2200E – New at Amazon
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Conveniently sized for just about any trip; expandable to carry all your gear // Brand new, fully adjustable sissy bar mounting system goes on in seconds over any size and style sissy bar pad; once adjusted for your size pad, you [...]

Buy Saddlemen Universal Bike Bag / Sissy Bar Bags Luggage SSR1900 – New at Amazon
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Convenient size, full of features, easy mounting and incredible value
Rugged, fully rigid construction holds bag shape even when empty
Fully adjustable mounting system includes two adjustable-length hooked bungees; mount onto sissy bar, luggage rack or back seat
Zip/hook-and-loop wide top [...]

Here are some great auction prices for a great deal.
Universal Sportbike Seat Tail Bag Luggage Expandable

US $29.96 End Date: Thursday Dec-31-2009 3:15:08 PSTBuy It Now for only: US $29.96Buy it now | Add to watch list

Vintage bicycle saddle seat tool bag, .. brooks ?

US $23.95 (12 Bids) End Date: Thursday Dec-31-2009 5:57:01 PSTBid [...]

Buy Saddlemen Roller W/Chrome Studs Sissy Bar Bag Luggage SDP2500DS at Amazon
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Sissy bar bag mounts easily to your motorcycle; can also double as a carry-on for air travel // Constructed of 1200-denier SaddleTuffTM with genuine leather fascia; SDP2500DS features chrome studs // State-of-the-art retractable handle // High-durability roller wheels can be covered [...]

Or will I have to pay more? I want it for commutes and log rides (with luggage) to the countryside.

Learn from an expert cyclist how to attach luggage to the back of a touring bicycle, and tips for attaching a rearview mirror in this free biking video clip.
Expert: Aaron Phillips
Bio: Aaron Phil…

Here are some great auction prices for a great deal.
New Bicycle Cycling Bike Wedge Seat Saddle Bag

US $2.70 End Date: Monday Oct-12-2009 0:48:17 PDTBuy It Now for only: US $2.70Buy it now | Add to watch list

BMW AIR BAG SENSOR MAT SEAT OCCUPANCY MAT

US $25.00 End Date: Monday Oct-12-2009 1:26:54 PDTBuy It Now for only: [...]

Here are some great auction prices for a great deal.
Universal Sportbike Seat Tail Bag Luggage Expandable

US $27.97 End Date: Tuesday Sep-22-2009 1:05:01 PDTBuy It Now for only: US $27.97Buy it now | Add to watch list

6′ Kiwi Green Oval Foam Bean Bag Chair love seat sac

US $215.00 (0 Bid) End Date: Tuesday Sep-22-2009 1:38:01 [...]